Verify the Identity $\frac { 1 + \cos x } { 1 - \cos x } - \frac { 1 - \cos x } { 1 + \cos x } = 4 \cot x \csc x$

Verify the identity. $\frac { 1 + \cos x } { 1 - \cos x } - \frac { 1 - \cos x } { 1 + \cos x } = 4 \cot x \csc x$